Yield loss and fungicide control of stem rust of wheat
R. Loughman A C , K. Jayasena B and J. Majewski AA Department of Agriculture, Western Australia, South Perth, WA 6151, Australia.
B Department of Agriculture, Western Australia, Albany, WA 6330, Australia.
C Corresponding author. Email: rloughman@agric.wa.gov.au
Australian Journal of Agricultural Research 56(1) 91-96 https://doi.org/10.1071/AR04126
Submitted: 7 June 2004 Accepted: 5 November 2004 Published: 31 January 2005
Abstract
Yield loss in wheat from natural infections with Puccinia graminis f.sp. tritici ranged from 10 to 45% in 3 experiments over 2 years. Fungicide reduced subsequent stem rust severity on plant parts that were only slightly infected at the time of fungicide application, but was not effective on plant parts that were more heavily infected when treated. Fungicide control of stem rust was economic in a range of situations. Fungicide applied at head emergence with low disease incidence (5% of stems) increased yield by 0.3 t/ha. When applied prior to head emergence with high disease incidence at low disease severity, yield increased by 0.8–1.5 t/ha, depending on duration of control. At a high disease incidence and moderate disease severity, yield increases of 0.4–0.6 t/ha were observed. Grain quality was also significantly improved with fungicide. Fungicide was more effective when applied immediately following detection compared with a 3-week delay. Folicur was more effective at reducing disease and increasing yield or quality than Impact or Triad.
Additional keywords: Puccinia graminis, grain quality, profit, resistance, triazole, timing, rate.
Acknowledgments
Staff at the Esperance Downs and Salmon Gums Research Stations provided excellent research support in establishment and harvest of these experiments. We are grateful to the wheat growers who co-operated in the conduct of these experiments. Andrea Hills (Department of Agriculture, Esperance) provided help in identifying experimental sites and liaising with growers. The work was supported by the Grains Research and Development Corporation (project DAW589). We thank Jane Speijers for statistical advice and Dorthe Jorgensen for assistance with the manuscript.
Bariana H, Puchakayala B, Standen G, Willey N, Wilson R
(2002) Identification of an uncharacterized adult plant leaf rust resistance gene in cultivar Westonia. ‘Plant Breeding for the 11th Millennium — Proceedings of the 12th Australian Plant Breeding Conference’. Perth. (Ed. Anon. )
p. 166. (Department of Agriculture Western Australia: Perth, W. Aust.)
Brown AGP, Reeves JT
(1975) Wheat rust epidemics. Journal of Agriculture, Western Australia (Series 4) 16, 72–73.
Dill-Macky R,
Rees RG, Platz GJ
(1990) Stem rust epidemics and their effects on grain yield and quality in Australian barley cultivars. Australian Journal of Agricultural Research 41, 1057–1063.
Dill-Macky R,
Rees RG, Platz GJ
(1991) Inoculum pressure and the development of stem rust epidemics in barley. Australian Journal of Agricultural Research 42, 769–777.
| Crossref | GoogleScholarGoogle Scholar |
Mayfield AH
(1985) Efficacies of fungicides for control of stem rust of wheat. Australian Journal of Agricultural Research 25, 440–443.
Peterson RF,
Campbell AB, Hannah AE
(1948) A diagrammatic scale for estimating rust intensity on leaves and stems of cereals. Canadian Journal of Research C 26, 496–500.
Rees RG, Syme JR
(1981) Epidemics of stem rust and their effects on grain yield in the wheat WW15 and some of its derivatives. Australian Journal of Agricultural Research 32, 725–730.
| Crossref | GoogleScholarGoogle Scholar |
Rowell JB
(1981) Control of stem rust on spring wheat by triadimefon and fenapanil. Plant Disease 65, 235–236.
Zadoks JC,
Chang TT, Konzak CF
(1974) A decimal code for the growth stages of cereals. Weed Research 14, 415–421.
